Another option is the new Denon D600's. The price keeps dipping below $300 every so often. The reviews are very mixed but the sound may be right up your alley and they do not need an amp to run. They will be loud and impact-full out of a portable device. They were made to compete with the likes of Beats and Sol and other celeb headphones. Not sure why they felt the need to dip down to that level but they did and it may be worth it to you to watch the amazon price or eBay because they will be back around $300 in the near future.
There are some used one's available now that may fit your needs.